It is known that 2,2-dichloropropionic acid as such and in a salt form is a herbicide; U.S. Pat. No. 2,642,354. It is also known that 2,2,3-trichloropropionic acid as such and in a salt form is effective as a herbicide; U.S. Pat. No. 2,807,530. Both the free acids and salts of these compounds are highly corrosive, relatively volatile and difficult to formulate as stable, non-corrosive liquid compositions. They are therefore usually used in solid particulate form, with or without a particulate solid carrier.